Welcome to my site of Microprocessor Projects. Having been in existence for nearly three years, hopefully there will be something for anybody with an interest in this subject, which includes ideas for suitable projects, most already tried and tested at some time, examples of simple hardware schematics and programming techniques, downloadable data sheets and of course fully documented ‘site projects’ incorporating three different popular 8 bit microprocessors, namely the Z80, the 8085 and the Mc6809.

Click on the images to the right for the associated site project. For the Z80 this is a digital clock, for the 8085, a simple Async comms project and for the 6809, a PC AT Keyboard interface unit with either serial or parallel outputs, or the new SITCOM 8085 based ‘training’ computer.

A Brief Overview of project‘SITCOM’

Uses only the most freely available components, expandable via a simple 40 pin header and programmable directly from a serial link to a host computer running a decent assembler program, such as the excellent freely downloadable SBASM from http://www.sbprojects.net

SITCOM

Having been a contructor of electronics projects for countless years, I have noticed that there doesn’t seem to be as much of a following for the hobby as there was whilst I was at school. One might have thought that the advent of the integrated circuit would have encouraged new interest from outsiders, but the reverse seems to have been the case, possibly due to the all-time low prices we are seeing, even for the most complex of electronic wizardry; and let’s face it, what incentive is there for a young newcomer to the hobby to construct a single transistor headphone radio, when some good intentioned family member or friend hands over a working discarded multiwaveband modern music system?

So what alternatives are now available to the experienced constructor, ignoring those projects which will cost far more to construct than buy ready made? The answer made it’s debut in the early 1970’s in the form of the silicon chip Microprocessor!

This singular component part could have been made for the home electronics constructor as it allows for the most ingenious and cunning home projects to be placed within the reach of anyone who has the patience to sit down and build. Granted, the construction may take some time and care, but the rewards can never be overshadowed by any commercially made alternative.

Hopefully for anybody with an interest in constructing their own micro-based projects, this site will act as a comprehensive RESOURCE of helpful information including:

Suggestions on what type of project can realistically be undertaken, and what is best left untried..

Follow the complete bare-board construction of a simple micro-based project from conception to finished item.

Data sheets, component information, as well as hints and tips on utilising the most common and popular microprocessors out there.

Constructional information. Tried and tested methods aside from those who have the facilities to make their own PCB’s (that I for one don’t have!!)

Software programming hints and tips, as well as ways of ‘blowing’ that program onto an EPROM and using the tested sample programs that have been proven to WORK!

You have no EPROM programmer? Well neither did I until I constructed my own!

SOME FURTHER FOOD FOR THOUGHT?

This is the mighty ‘Mentor’. What an ‘unusual’ job I made on that housing! (proves that I’m not much of a carpenter..) An interesting exercise in designing a universal piece of test gear to do everything I could think of that I’d ever need.. well almost everything.. I still use it occasonally, more often than not for it’s serial port testing facilities. (It even included a couple of games for the kiddies!) Some useful info available on this site for those interested in their own version.

Ah! That’s more like it! Something in a proper box - and this is only the prototype! Sold like hot cakes as the Stopwatch III. Designed for the Dinghy sailing fraternity, with programmable handicap starts, countdown timer, memory and more! Full details and software available here up for grabs!

There are a few concept demonstrators here too. In the example to the right we have a ‘Televideo’ receiver unit that builds up a composite TV picture from the serial digital data coming in from a twisted pair. Interested? Some helpful stuff here on this site if you dare!

Here is the concept model that I used to create one of the site’s own micro based projects. In this picture the board is running the clock software that we’ll be using in the finished constructional article. By condensing the circuit somewhat, the RAM, the clock dividers and the I/O - memory decoder will be the first to go..!.

Our last example here is in fact a cable tester prototype. Note that once again, in keeping with our clock in the previous image, there is no RAM required for the circuit to operate correctly; thus keeping the complexity and cost to a minimum.

If you’ve read down as far as this then you may well be interested in looking a bit deeper into the idea of constructing your own microprocessor based project? Don’t forget that the examples shown above were simply the projects that I was able to lay my hands on with the minimum of effort. In my loft I have a plethora of other micro based projects, ranging from diagnostic tools, a universal data storage system using floppy disks, to PROM programmers and full sized electronic side show games! Simply click on the links down the left hand side of the page to select each topic that interests you. Enjoy!